Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description still adds real behavioral context beyond that: it recomputes rather than reads stored state, reports counts and the head hash, and explicitly discloses that record contents are not exposed — a privacy/exposure trait annotations cannot convey.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

A single front-loaded sentence with the verb first and the outputs enumerated as a compact list; nothing is wasted. Minor cost is the slightly run-on colon construction, but it stays readable and scannable.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

There is no output schema, so the description must carry the return values — and it does, naming the integrity result, record count, rollback flags, and head hash. For a one-parameter, read-only tool with full annotation coverage, nothing an agent needs before calling is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% and the single parameter already documents both accepted forms (car_... vehicle_id or 17-character VIN). The description adds no syntax, format, or validation detail beyond that, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

"Recompute the vehicle's hash chain" gives a specific verb and resource, and the colon list enumerates exactly what the caller gets back (integrity status, record count, rollback flag count, head hash). The closing clause "Shows no record contents" further pins down what kind of tool this is versus a content-listing tool.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is implied rather than stated: the verification framing makes the when-to-use obvious, and "Shows no record contents" hints that a content-reading tool is the alternative. However, no sibling is named and no explicit when-not-to-use condition or prerequisite is given.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.